• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * nghttp2 - HTTP/2 C Library
3  *
4  * Copyright (c) 2012 Tatsuhiro Tsujikawa
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining
7  * a copy of this software and associated documentation files (the
8  * "Software"), to deal in the Software without restriction, including
9  * without limitation the rights to use, copy, modify, merge, publish,
10  * distribute, sublicense, and/or sell copies of the Software, and to
11  * permit persons to whom the Software is furnished to do so, subject to
12  * the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be
15  * included in all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
21  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
22  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
23  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24  */
25 #ifndef SHRPX_TLS_H
26 #define SHRPX_TLS_H
27 
28 #include "shrpx.h"
29 
30 #include <vector>
31 #include <mutex>
32 
33 #include <openssl/ssl.h>
34 #include <openssl/err.h>
35 
36 #include <ev.h>
37 
38 #ifdef HAVE_NEVERBLEED
39 #  include <neverbleed.h>
40 #endif // HAVE_NEVERBLEED
41 
42 #include "network.h"
43 #include "shrpx_config.h"
44 #include "shrpx_router.h"
45 
46 namespace shrpx {
47 
48 class ClientHandler;
49 class Worker;
50 class DownstreamConnectionPool;
51 struct DownstreamAddr;
52 struct UpstreamAddr;
53 
54 namespace tls {
55 
56 struct TLSSessionCache {
57   // ASN1 representation of SSL_SESSION object.  See
58   // i2d_SSL_SESSION(3SSL).
59   std::vector<uint8_t> session_data;
60   // The last time stamp when this cache entry is created or updated.
61   ev_tstamp last_updated;
62 };
63 
64 // This struct stores the additional information per SSL_CTX.  This is
65 // attached to SSL_CTX using SSL_CTX_set_app_data().
66 struct TLSContextData {
67   // SCT data formatted so that this can be directly sent as
68   // extension_data of signed_certificate_timestamp.
69   std::vector<uint8_t> sct_data;
70 #ifndef HAVE_ATOMIC_STD_SHARED_PTR
71   // Protects ocsp_data;
72   std::mutex mu;
73 #endif // !HAVE_ATOMIC_STD_SHARED_PTR
74   // OCSP response
75   std::shared_ptr<std::vector<uint8_t>> ocsp_data;
76 
77   // Path to certificate file
78   const char *cert_file;
79 };
80 
81 // Create server side SSL_CTX
82 SSL_CTX *create_ssl_context(const char *private_key_file, const char *cert_file,
83                             const std::vector<uint8_t> &sct_data
84 
85 #ifdef HAVE_NEVERBLEED
86                             ,
87                             neverbleed_t *nb
88 #endif // HAVE_NEVERBLEED
89 );
90 
91 // Create client side SSL_CTX.  This does not configure ALPN settings.
92 // |next_proto_select_cb| is for NPN.
93 SSL_CTX *create_ssl_client_context(
94 #ifdef HAVE_NEVERBLEED
95     neverbleed_t *nb,
96 #endif // HAVE_NEVERBLEED
97     const StringRef &cacert, const StringRef &cert_file,
98     const StringRef &private_key_file,
99     int (*next_proto_select_cb)(SSL *s, unsigned char **out,
100                                 unsigned char *outlen, const unsigned char *in,
101                                 unsigned int inlen, void *arg));
102 
103 ClientHandler *accept_connection(Worker *worker, int fd, sockaddr *addr,
104                                  int addrlen, const UpstreamAddr *faddr);
105 
106 // Check peer's certificate against given |address| and |host|.
107 int check_cert(SSL *ssl, const Address *addr, const StringRef &host);
108 // Check peer's certificate against given host name described in
109 // |addr| and numeric address in |raddr|.  Note that |raddr| might not
110 // point to &addr->addr.
111 int check_cert(SSL *ssl, const DownstreamAddr *addr, const Address *raddr);
112 
113 struct WildcardRevPrefix {
WildcardRevPrefixWildcardRevPrefix114   WildcardRevPrefix(const StringRef &prefix, size_t idx)
115       : prefix(std::begin(prefix), std::end(prefix)), idx(idx) {}
116 
117   // "Prefix" of wildcard pattern.  It is reversed from original form.
118   // For example, if the original wildcard is "test*.nghttp2.org",
119   // prefix would be "tset".
120   ImmutableString prefix;
121   // The index of SSL_CTX.  See ConnectionHandler::get_ssl_ctx().
122   size_t idx;
123 };
124 
125 struct WildcardPattern {
126   // Wildcard host sharing only suffix is probably rare, so we just do
127   // linear search.
128   std::vector<WildcardRevPrefix> rev_prefix;
129 };
130 
131 class CertLookupTree {
132 public:
133   CertLookupTree();
134 
135   // Adds hostname pattern |hostname| to the lookup tree, associating
136   // value |index|.  When the queried host matches this pattern,
137   // |index| is returned.  We support wildcard pattern.  The left most
138   // '*' is considered as wildcard character, and it must match at
139   // least one character.  If the same pattern has been already added,
140   // this function does not alter the tree, and returns the existing
141   // matching index.
142   //
143   // The caller should lower-case |hostname| since this function does
144   // do that, and lookup function performs case-sensitive match.
145   //
146   // TODO Treat wildcard pattern described as RFC 6125.
147   //
148   // This function returns the index.  It returns -1 if it fails
149   // (e.g., hostname is too long).  If the returned index equals to
150   // |index|, then hostname is added to the tree with the value
151   // |index|.  If it is not -1, and does not equal to |index|, same
152   // hostname has already been added to the tree.
153   ssize_t add_cert(const StringRef &hostname, size_t index);
154 
155   // Looks up index using the given |hostname|.  The exact match takes
156   // precedence over wildcard match.  For wildcard match, longest
157   // match (sum of matched suffix and prefix length in bytes) is
158   // preferred, breaking a tie with longer suffix.
159   //
160   // The caller should lower-case |hostname| since this function
161   // performs case-sensitive match.
162   ssize_t lookup(const StringRef &hostname);
163 
164   // Dumps the contents of this lookup tree to stderr.
165   void dump() const;
166 
167 private:
168   // Exact match
169   Router router_;
170   // Wildcard reversed suffix match.  The returned index is into
171   // wildcard_patterns_.
172   Router rev_wildcard_router_;
173   // Stores wildcard suffix patterns.
174   std::vector<WildcardPattern> wildcard_patterns_;
175 };
176 
177 // Adds hostnames in certificate in |ssl_ctx| to lookup tree |lt|.
178 // The subjectAltNames and commonName are considered as eligible
179 // hostname.  If there is at least one dNSName in subjectAltNames,
180 // commonName is not considered.  |ssl_ctx| is also added to
181 // |indexed_ssl_ctx|.  This function returns 0 if it succeeds, or -1.
182 int cert_lookup_tree_add_ssl_ctx(
183     CertLookupTree *lt, std::vector<std::vector<SSL_CTX *>> &indexed_ssl_ctx,
184     SSL_CTX *ssl_ctx);
185 
186 // Returns true if |proto| is included in the
187 // protocol list |protos|.
188 bool in_proto_list(const std::vector<StringRef> &protos,
189                    const StringRef &proto);
190 
191 // Returns true if security requirement for HTTP/2 is fulfilled.
192 bool check_http2_requirement(SSL *ssl);
193 
194 // Returns SSL/TLS option mask to disable SSL/TLS protocol version not
195 // included in |tls_proto_list|.  The returned mask can be directly
196 // passed to SSL_CTX_set_options().
197 long int create_tls_proto_mask(const std::vector<StringRef> &tls_proto_list);
198 
199 int set_alpn_prefs(std::vector<unsigned char> &out,
200                    const std::vector<StringRef> &protos);
201 
202 // Setups server side SSL_CTX.  This function inspects get_config()
203 // and if upstream_no_tls is true, returns nullptr.  Otherwise
204 // construct default SSL_CTX.  If subcerts are available
205 // (get_config()->subcerts), caller should provide CertLookupTree
206 // object as |cert_tree| parameter, otherwise SNI does not work.  All
207 // the created SSL_CTX is stored into |all_ssl_ctx|.  They are also
208 // added to |indexed_ssl_ctx|.  |cert_tree| uses its index to
209 // associate hostname to the SSL_CTX.
210 SSL_CTX *
211 setup_server_ssl_context(std::vector<SSL_CTX *> &all_ssl_ctx,
212                          std::vector<std::vector<SSL_CTX *>> &indexed_ssl_ctx,
213                          CertLookupTree *cert_tree
214 #ifdef HAVE_NEVERBLEED
215                          ,
216                          neverbleed_t *nb
217 #endif // HAVE_NEVERBLEED
218 );
219 
220 // Setups client side SSL_CTX.
221 SSL_CTX *setup_downstream_client_ssl_context(
222 #ifdef HAVE_NEVERBLEED
223     neverbleed_t *nb
224 #endif // HAVE_NEVERBLEED
225 );
226 
227 // Sets ALPN settings in |SSL| suitable for HTTP/2 use.
228 void setup_downstream_http2_alpn(SSL *ssl);
229 // Sets ALPN settings in |SSL| suitable for HTTP/1.1 use.
230 void setup_downstream_http1_alpn(SSL *ssl);
231 
232 // Creates CertLookupTree.  If frontend is configured not to use TLS,
233 // this function returns nullptr.
234 std::unique_ptr<CertLookupTree> create_cert_lookup_tree();
235 
236 SSL *create_ssl(SSL_CTX *ssl_ctx);
237 
238 // Returns true if SSL/TLS is enabled on upstream
239 bool upstream_tls_enabled(const ConnectionConfig &connconf);
240 
241 // Performs TLS hostname match.  |pattern| can contain wildcard
242 // character '*', which matches prefix of target hostname.  There are
243 // several restrictions to make wildcard work.  The matching algorithm
244 // is based on RFC 6125.
245 bool tls_hostname_match(const StringRef &pattern, const StringRef &hostname);
246 
247 // Caches |session|.  |session| is serialized into ASN1
248 // representation, and stored.  |t| is used as a time stamp.
249 // Depending on the existing cache's time stamp, |session| might not
250 // be cached.
251 void try_cache_tls_session(TLSSessionCache *cache, SSL_SESSION *session,
252                            ev_tstamp t);
253 
254 // Returns cached session associated |addr|.  If no cache entry is
255 // found associated to |addr|, nullptr will be returned.
256 SSL_SESSION *reuse_tls_session(const TLSSessionCache &addr);
257 
258 // Loads certificate form file |filename|.  The caller should delete
259 // the returned object using X509_free().
260 X509 *load_certificate(const char *filename);
261 
262 // Returns TLS version from |v|.  The returned value is defined in
263 // OpenSSL header file.  This function returns -1 if |v| is not valid
264 // TLS version string.
265 int proto_version_from_string(const StringRef &v);
266 
267 // Verifies OCSP response |ocsp_resp| of length |ocsp_resplen|.  This
268 // function returns 0 if it succeeds, or -1.
269 int verify_ocsp_response(SSL_CTX *ssl_ctx, const uint8_t *ocsp_resp,
270                          size_t ocsp_resplen);
271 
272 // Stores fingerprint of |x| in |dst| of length |dstlen|.  |md|
273 // specifies hash function to use, and |dstlen| must be large enough
274 // to include hash value (e.g., 32 bytes for SHA-256).  This function
275 // returns the number of bytes written in |dst|, or -1.
276 ssize_t get_x509_fingerprint(uint8_t *dst, size_t dstlen, const X509 *x,
277                              const EVP_MD *md);
278 
279 // Returns subject name of |x|.  If this function fails to get subject
280 // name, it returns an empty string.
281 StringRef get_x509_subject_name(BlockAllocator &balloc, X509 *x);
282 
283 // Returns issuer name of |x|.  If this function fails to get issuer
284 // name, it returns an empty string.
285 StringRef get_x509_issuer_name(BlockAllocator &balloc, X509 *x);
286 
287 // Returns serial number of |x|.  If this function fails to get serial
288 // number, it returns an empty string.  number
289 StringRef get_x509_serial(BlockAllocator &balloc, X509 *x);
290 
291 // Fills NotBefore of |x| in |t|.  This function returns 0 if it
292 // succeeds, or -1.
293 int get_x509_not_before(time_t &t, X509 *x);
294 
295 // Fills NotAfter of |x| in |t|.  This function returns 0 if it
296 // succeeds, or -1.
297 int get_x509_not_after(time_t &t, X509 *x);
298 
299 } // namespace tls
300 
301 } // namespace shrpx
302 
303 #endif // SHRPX_TLS_H
304